Heater system



May 31, 1949- v. N. TRAMoNTiNl 2,471,846

HEATER SYSTEMl Filed April 1o, 1946 50 gg ZQ Patented May 31,;1949

FFICE HEATER SYSTEM Vernon N. Tramontini, Indianapolis, Ind., as-

signor to Stewart-Warner Corporation, Chicago, Ill., acorporation of Virginia Application April 10, 11946, Serial N0. 661,096

i Claims. l

The present invention relates to heating systems and, more particularly, to a heating system `for an automotive vehicle which includes a hot air heater supplied with the same fuel as is used by the engine of the vehicle, usually gasoline.

One of the objects of the present invention is to provide an improved heating system for an automotive vehicle which uses a highly volatile fuel, such as gasoline.

Another object of the present invention is to provide a heating system of the above type including novel mechanism for preventing the formation of bubbles in the line which conveys fuel to the heater.

Another object is to provide a heating system of the above type with an arrangement for removing bubbles from the fuel before the fuel is passed into a branch line leading to the heater. Yet another object of the present invention is to provide an improved heating system which receives fuel from the engine fuel pump at normal pump pressure and which includes an arrangement for insuring that gas bubbles do not reach the heater in suicient quantity to interfere with heater operation.

Yet another object of the present invention is to provide all of the above at low cost and with mechanically simple mechanism.

Other objects and advantages will become apparent from the following description of a preferred `embodiment of my invention.

. In the drawings, in which similar characters of reference refer to similar parts throughout the several views:

Fig. 1 is a side view of an automobile heater and engine and the associated mechanism usually found in the engine compartment;

Fig. 2 is a side elevation of a device for preventing fuel bubbles from reaching the heater. In this figure a portion of the side wall of the device is broken away to show the interior thereof in medial section; and

Fig 3 is an end View of a portion of the device illustrated in Fig. 2.

In Fig. 1 of the drawings I have shown an auto-` mobile engine l located within an engine compartment I2, the latter being separated from the drivers compartment i4 by a partition or dash I6. Fuel is brought into `the engine compartment through a line lil which is connected to a fuel pump 20 illustrated as being of the common cam shaft driven type. Pumps of other types can of course be used. From the pump, the fuel passes through a conventional filter and settling y.bowl 2.2 .and the-110 t0 a heater fuel take-oit 2 fitting Ell. From there the fuel flows by a line 26 to the engine carburetor 28.

The heater Sil may be of the type referred to in my copencling application entitled Heater controls, Serial No. 633,733, which was filed Deway of cember 8, i945. Such a heater receives air `for ventilation from an open ended duct 32 located to receive air passing through the radiator grill Sii. Air from the duct 32 is taken into the inlet of a blower 36 driven by an electric motor, not shown, and passes from the blower into the heater Sil. Within the heater the temperature of the air is raised, after which it is passed into a hot air duct 33 leading to the drivers compartment ifi- In Fig. 1 I have shown the air as merely passing into the drivers compartment by Way of a chamber lil having a louvered opening 42. It will be appreciated, however, that more extensive hot air distributing ductwork in the automobile may be used, if desired.

The heater til is intended to receive fuel in liquid form and is so constructed that it meters fuel to 'the burner at the proper rate when fuel is delivered to the heater `fuel connection at substantially the pressure produced by the pump 20.

The heater fuel take-off 24 comprises a T- shaped fitting ld having a straight-through passage li and an intersecting branch passage 48. One end of the straight-through passage, for instance, the end 5t, is equipped With fittings 52 for connection 'to the automobile fuel line 54 which receives fuel from the outlet connection of the filter 2r. The other end of the straightthrough passage is connected by fittings 56 to the fuel line 26 leading to the engine carburetor. The branch passage it is connected to the upper end of a downwardly extending tubular member 58, which may be a piece of one-eighth inch standard pipe approximately three to four inches long. The lower end of the tubular element 58 is connected by a tting to to the heater fuel line t2. This latter fuel line preferably, :for convenience in handling and from the `standpoint of cost, is formed one-eighth inch outside diameter standard brass or copper tubing and leads directly to the heater fuel connection. Standard tubing of this outside diameter has an inside-diameter of approximately one-sixteenth of an inch.

With this arrangement it is seen that the fuel pump it supplies fuel by way of the filter and settling bowl 22 to both the engine carburetor 28 and also the heater 3l). It has been found by tests that under some conditions, if the heater fuel line $52 is connected directly to the engine fuel line 26 by means of simple T, probably because of the small inside diameter of the tube 62 and because the rate of fuel consumption by the heater is so low and because of the elevated. temperature prevailing within the engine compartment I2, fuel bubbles are likely to form within the branch 52 and these bubbles when they reach the heater 33 frequently interrupt combustion or at least make heater operation rough. Provision of the special fuel take-off fitting 24, however, obviates this diiiiculty, probably for the following reason. It provides a vertical column of fuel within the comparatively large diameter passage 64 of the downwardly extending tubular element 53. The rate of fuel consumption by the heater is so low that the column of fuel within the passage 64 moves downwardly at Very 10W Velocity. In fact, it may be considered as lessentially a stationary column of nonturbulent fuel, turbulence in the column being prevented by the large length-to-width ratio of the passage or chamber (i4. The fuel within this passage 6d is raised substantially to the temperature of the engine compartment and bubbles which form in the column float upwardly into the transverse passage it and are carried to the engine carburetor through the fuel line 26. In the engine carburetor they are harmless, since the bubbles rise to the top of the carburetor float bowl and are carried :olf through the conventional fio-at bowl vent system incorporated in all carburetors of this type.

Removal of bubbles while the fuel is within the passage 613 reduces the boiling point thereof,

- Fuel which eventually reaches the lower end of the passage E52, therefore, will be composed primarily of the high boiling point fractions and will pass through the small tube E52 leading to the heater without appreciable additional formation of vapor. The fuel arriving at the heater, therefore, contains practically no components in the vapor'phase, and, thus, heater operation will be steady at the output rate for which the heating system is designed.

Having described my invention, what I claim as new and useful and desireto secure by Letters Patent of the United States is:

l. A fuel feeding system for an automotive vehicle having a heater which burns the same fuel as the automotive vehicle engine, said fuel being highly volatile, comprising a fuel pump, means to supply fuel to said pump, an engine carburetor, a float bowl for said carburetor, a fuel line leading from said fuel pump to said float bowl of said engine carburetor, a fitting for withdrawing fuel from said line at a point between said pump and said carburetor, said fitting having a downwardly extending passage.

of large diameter to provide a reservoir of high length-to-width ratio, and a heater fuel line of small diameter connected to the lower end of said passage at one end and to said heater at the other end, so that light ends in the fuel which vaporize in said passage will be carried to said carburetor fioat bowl rather than to said heater.

2. A fuel feeding system for an automotive vehicle having a heater which burns the same fuel as the automotive vehicle engine, said fuel being highly volatile, comprising a fuel pump, means to supply fuel to said pump, an engine carburetor, a float bowl for said carburetor, an engine fuel .4 line leading from said fuel pump to said float bowl of said engine carburetor, a fitting for withdrawing fuel from said engine line at a point between said pump and said carburetor, said fitting including means forming a passage connected to said engine fuel line and to an outlet opening lower than said engine fuel line, a heater fuel line of ,small diameter Iconnected itc said outlet opening at yone end and .to .the heater at the other end, and said passage including a reservoir fof sufficient cross section in proportion to the rate of flow of fuel to said heater that bubbles forming in said passage will rise against the direction of flow .of fuel therethrough so that said bubbles return tosaid engine fuel line, said reservoir being 4adapted to inhibit fuel turbulence therein.

3. `In a fuel feeding system for an automotive vehicle having a heater which burns the same fuel as the vehicle engine, said fuel being highlyvolatile, said .vehiclehaving -a fuel tank, a .carburetor, an engine fuel line leading from said tank to said carburetor, means for causing fuel to iiow through said line from said tank to said carburetor, vand a small diameter heater fuel line; a fitting for withdrawing fuel .from said engine line, the interior of said .fitting forming a reservoir of larger capacity than a simil-ar length of said engine line, means forming passages into and out of said reservoir adapted to be connected to said engine line whereby said fitting may be interposed in said line', and means form-ing an outlet opening communicating with said reservoir in said fitting below said passages adapted to be connected to said heater line, said reservoir 'being of a size sufcient to retard the rate of fuel vflow therethrough to permit bubbles in said stream to rise to the top of .said reservoir .and follow the iiow of fuel to said carburetor, while fuel at said heater outlet opening at the bottom of said fitting is substantially free of bubbles.

4. In a fuel feeding system for an automotive vehicle having a heater which burns the `same fuel as the vehicle engine, said fuel being highly volatile, said vehicle having a fuel tank, a carburetor, an engine fuel line leading from said tank to said carburetor, means for causing fuel to iiow through said line from said tank to said carburetor, and a small diameter heater fuel line; a fitting for withdrawing fuel from said engine line for said heater, said fitting having means constituting a passage to be interposed in said engine line, said passage having an enlarged portion therein constituting a reservoir whereby the velocity of fuel flow is decreased, means forming an outlet communicating with said reservoir below said passage adapted to be connected to said heater line, and means interposed between said outlet and said reservoir whereby the entrance of bubbles into said outlet is substantially prevented.

VERNON N. TRAMONTINI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,207,776 Black July 16, 1940 2,270,956 McCollum et al Jan. 27, 1942 2,306,134 McCollum et al Dec. 22, 1942 

